A new survey from human-resources services firm Aon Hewitt found that companies are spending a record share of their payroll on performance-based bonuses, signaling a shift away from longer-term salary increases.

The 1,064 companies polled, in industries like energy, consumer products, banking and accounting, are devoting an average of 12.7% of their 2014 payrolls to so-called variable pay, which includes things like bonuses paid out when employees or companies meet specific goals. The figures apply to salaried workers exempt from overtime pay.

More than 90% of those companies offer a variable pay program, as opposed to 78% of the companies polled in a 2005 survey. That year, variable pay accounted for 11.4% of payroll.

The trend can be attributed, in part, to the economic recovery, said Kenan Abosch, who leads the compensation consulting practice at Aon Hewitt. Companies are getting a bit more confident about their outlook and the labor market is heating up, leaving firms searching for ways to attract and retain talent.

But there’s still hesitancy when it comes to making significant long-term investments in pay packages. Companies are “not willing to spend on things that they’ll have to live with,” Absoch said.

Performance-based pay lets firms reward employees without committing to the annual expenses that across-the-board salary increases bring. Employers get more flexibility and control when it comes to pay, but they can still “wrap their arms around their top performers and high-potential performers,” Abosch said. And pay-for-performance packages push workers to deliver results.

Meanwhile, the survey found that base salary increases stood at 2.9% for salaried workers exempt from overtime pay and are expected to increase slightly to 3% next year. They’ve been climbing since 2009 but have yet to reach 2008’s rate of 3.9%.

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